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Old 01-17-2012, 08:20 PM
gary@germanautosolutions's Avatar
gary@germanautosolutions gary@germanautosolutions is offline
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Location: Grand Rapids, Michigan
Join Date: Jul 2010
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Mein Auto: E39 528i, E60 M5
Here are the preliminary install instructions. All feedback welcome.

What comes in the kit. A piece of safety wire and a cotton swab will also be included.

This is where to pry the access cover off. You need a similar size screwdriver.

What's under the cover.

You need to pry the retaining clip off.

Work the clip off by prying back and forth from alternate sides.

This is the best place to pry the vacuum lever up. It comes off easily.

Next you wire this out of the way. Not necessary but very helpful.

The best way to pop the bell crank lever out is to pry here. Again you need the proper size screw driver to fit in here. You need to get between the seal boss and the lever, then pry and twist. If you have a used DISA this piece may just fall out or be able to be pulled out by hand. If you are retrofitting a new DISA you will need to pry it out.

Here is the bell crank. This is a new one, a used one may look different depending how much plastic has been worn away.

This is a critical proceedure if your DISA is new or the pin is still fully seated. The pin head is very thin and sits flush with the top of the support bearing, so there isn't an easy way to grab it. You need to get a proper size screwdriver blade that just fits between the top edge of the flapper valve and the underside of the framework at the location shown. Position the blade so when you twist the scewdriver, it will pry up on the framework. Again a used DISA may have the pin already falling out and you can skip this step. If you have one with the pin fully seated, be careful not to damage the framework.

This is what the pin head looks like after prying the framework. You need only pry enough to form a gap under the head.

Now you can remove the pin with a pair of diagonal cutters.

This is how long the steel pin is. It's pressed in pretty tightly on a new unit. This is what has ruined a few engines after it fell out and went through the intake runner and into the cumbustion chamber.

The flapper can now be slid out of the frame work.

Once you have the flapper and bellcrank removed you will want to clean the rest of the DISA. I recommend using a full strength industrial cleaner like Simple Green or Purple Power from Auto Zone. I would avoid brake cleaner of solvents as they make make the plastic more brittle. Note the little hole being pointed to, this is the vacuum port hole that actuates the DISA. Plug this with a tooth pick or something to avoid getting excess water into the chamber. Use a tooth brush (the wife's, if it's her car) and the cleaner and work at it until it's acceptably clean to you.

Once the DISA is clean and dry you are ready to begin reassembly. Apply a nice glob of the supplied grease to the cotton swab.

Apply the grease to the inside lip of the bell crank seal as shown.

Apply a little around the perimeter of the bellcrank shaft.

Note the rotation as shown and install the new lubed up bellcrank.

Sorry some of the pictures are a little out of focus but you can still see what needs to be seen. Push the bell crank all the way in as far as it will go. It should look like this and will probably have grease all over the tapered hex from pushing it through. While keeping the bellcrank pushed in with your finger, completely clean the protruding hex taper with a clean cloth and solvent. Brake cleaner, acetone, etc.

Next, with a clean finger, push the bellcrank back until it's flush with the surface as shown. The goal is to keep it centered in the hole so that you don't get any grease on the taper again. The seal will hold it in place.

Apply some of the supplied threadlock to the end of the cotton swab (preferably the non-greased end) as shown.

Then wipe a thin film inside the female hex pocket of the new flapper valve. Don't over do it, it should just be wet on the sides.

Now you can slide the new valve in place. This is the only orientation that will allow the flapper to slide in due to it's shape. It goes in from the side with the vacuum hole with the flapper positioned as shown. It's designed to be a precision fit so it needs to be straight in order to slide in.

Flapper in place.

If you want you can temporarily replace the steel pin and hold it in with your finger while you push the bellcrank into place. Not necessary, but it helps to keep that end centered while working on the other.

This is the position you want the flapper to be in while pushing the bellcrank into place. 90 degrees to the framework.

Make sure that the bellcrank is aligned like this and the flapper is 90 degrees to the framework, then push the bellcrank into place.

Install the lock washer onto the new pivot screw.

Apply one good size drop of threadlock to the end of the thread.

Anything more than this is unnecessary. Excess theadlock could try to make it's way into the end bearing so don't feel the need to over do it.

You can now install the pivot screw. You may want to look down the end of the support bearing hole to help with aligning the end of the pivot screw with the hole. You will want to hold the flapper in the closed postion while tightening the screw with a 5mm allen wrench or hex driver. You want the screw very tight to fully seat the tapered surfaces together. Once the screw is tight, make sure the flapper rotates freely back and forth.

You can now put the vacuum pot lever back over the bellcrank pin and push the retaining clip back on.

Reinstall the plastic cover and your finished. Double check that the flapper will rotate from the 90 degree postion to the closed position, then when released return to the 90 degree position on it's own.

I don't know if all the detail shown here makes this seem like an involved job? It's actually pretty straight forward and very do-able for anyone with decent mechanical skills and a few basic hand tools. What do you all think?

"I'm a little rascal on my Little Rascal"
- unknown
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